Switch
by orangeyhairedimmortal
Summary: Captain Kurotsuchi has developed a serum that will make anyone with a bankai's power or higher able to strengthen tenfold when activated. Nothing could go wrong except for the fact that when the power is activated, not only does it give the Soul Reaper's power ten fold, it also causes them to change gender. GenderBender - No yaoi/yuri
1. Chapter 1

i promise that i am thinking about reaction. i really am... so to anyone who is waiting on it, i promise it's still active

* * *

Captain Kurotsuchi sucked up some blue liquid into a dropper and then dropped one tiny dot of it into a golden liquid, a green smoke coming up the beaker. Mayuri smiled and looked at the slightly green liquid.

"Yes, this should do it…"

"Captain?" Akon said, coming up behind his captain. "What is that?"

"Since there has been so many fights going on here in the Soul Society and we as captains haven't been at our best so it seems. In fact, we have been getting our asses kicked to put it bluntly. I have made a serum that will give us strength tenfold in our bankai forms. We will be faster, stronger, have higher dexterity, and be prone to less damage."

"That sounds amazing. Do you have enough for all the captains?" the horned shinigami asked.

"I have decided to put it in a gas form so that I may spread it to all the captains and lieutenants without having to make a whole slew of the serum. It will makes things easier to distribute."

Akon nodded and Mayuri put a stopper on the beaker and put it in a containment field.

"It's not finished. There is one more ingredient that I need to make sure the serum detects gender."

"Gender?"

"Yes… I must go find the component that I need."

Mayuri walked off and Akon looked around to see if anyone was watching. Everyone seemed to be doing their own thing; Nemu had gone off with Mayuri and Hiyosu was watching the screens with too much enthusiasm as always. Akon reached into the containment field and pulled out the serum, looking around at it. It was an interesting looking liquid, golden with little specks of blue floating in it like shining stars of glitter. Akon lifted it up to see it against the light when a noise startled him and he dropped it. He looked at the liquid as it spread out below him and wafted into a thin gaseous smoke, heading toward the vents of the Research and Development Center.

Akon gulped and walked away, acting like nothing happened.

* * *

"Captain Kurotsuchi, I hear that you have something to share with us." Head Captain Yamamoto said at the captain's meeting.

"Yes. We seem to have been getting defeated a lot easier than usual these past couple of big fights. Not that some of us haven't been on our game but we have been able to be put down and having to resort to our bankais so easily. Even in our bankai states, the enemy seems to be having the upper hand unless two or more captains combine their bankais. It find that disturbing."

"As do I… What is it that you have then, Captain Kurotsuchi?"

"I have made a serum that will enhance anyone with a bankai's power or higher be enhanced tenfold. Greater power, dexterity… We may have to resort to our bankais faster, but in that state we will be unstoppable."

Yamamoto rubbed his chin and thought about it for a moment.

"And this is safe?"

"Yes. It's safe for everyone but will only affect those with bankai power or higher. I have to add one more component to the serum so that the serum will differentiate between males and females but other than that, it is complete."

"Hmm. Bring this serum to me and we will evaluate it to see if it is good enough for us."

Mayuri bowed and left to go back to the Research and Development Center.

Mayuri was going to kill Akon. Whether it was by an experiment or because he thoroughly pissed off. He stared at the horned man as Akon cringed in the corner, wondering what his captain would do to him.

"You _dropped_ my serum?"

"I'm so sorry, Sir! I was just looking at it and then something scared me and I dropped it. I knew I shouldn't have been looking at it but I was just so curious and…"

Mayuri grabbed Akon by the face and looked at him with a crazy expression.

"So you took it upon yourself to look at my things? I should kill you… But now that I think about it, this will be an interesting experiment. I wonder what will happen when anyone uses their bankai after this."

"Are you going to try it out?"

"Normally I would, considering I think of myself as the ultimate experiment, but this time I think I will observe. If my thoughts are correct then I _definitely_ want to see how this goes before I try it out."

Akon didn't like the sound of that nor did he like the look of gears turning in his captain's head. He almost wished he'd never gotten a hold of that serum. Mayuri nodded to himself and began to chuckle as he walked over to his lab station.

* * *

Renji Arabai, Ikakku Madarame, and Yumachika Ayasegawa walked along the barracks of the Seireitei when they noticed an eerie looking cloud coming over the horizon from Squad Twelve.

"What is that?" Ikakku asked with a turn of his head.

"It looks ominous but at least the color is pleasant to look at." Yumachika said, putting his hand to his chin.

Renji rolled his eyes at him. "Is that all you think about?"

Yumachika looked at him and then flipped his short bob back in a flamboyant manner.

"My dear Renji, if something is beautiful, it is more worthwhile to look at than something ugly. I'm still trying to keep a straight face when I look at _you_ and it still hasn't gotten better on my eyes. Unfortunately, Ikkaku likes to hang out with you and what can I do?"

"Leave. I don't need this from some frilly fifth seat-"

Without their knowledge the cloud came toward them and finally engulfed them. They coughed and swatted the cloud of smoke away.

"Ugh, it stinks!" Renji said, gagging on the smell.

"I take it back. This is a horrible, deceiving cloud!" Yumachika said with a screwed up face.

They coughed for another minute or two until it cleared all the way and they looked around.

"Well, nothing happened to us. I hope we don't get turned into something from that crazy guy's experiments." Ikkaku said with a frown.

The other two nodded and began walking down the path again.

* * *

hey guys, first genderbend so please be kind to me!


	2. Chapter 2

Ichigo Kurosaki, Substitute Soul Reaper, was walking with Rukia and Orihime to town so that they could get some supplies for Urahara's Shop. Ichigo didn't know what he was wanting, since he was very vague as usual, but getting out and being a little normal was nice for a change.

"We should get ice cream and cookies and milk." Orihime said as she carried her bag in front of her, her equally orange hair getting in her face from the wind.

She wiped it away and Ichigo smiled at her. He wished out of all the bravery he had in himself, he wished that he could tell her that he liked her and wanted to be with her. But he had too much that was on his mind and he felt like doing that would only make things worse for both he and for Orihime.

Rukia shook her head at Orihime's answer.

"No, Urahara-san will most likely want salted things. Chips, sushi, or something like that."

Orihime nodded her head fervently. "Yes, that's true too!"

Suddenly, the Senkaimon appeared before them and Ichigo stopped, taking a small stance at the unexpected presence of the Senkaimon. The doors opened and two people ran out quickly and the one practically ran Ichigo over as they both fell to the ground.

"You need to watch where you're going!" Ichigo yelled but looked up and saw that it was a very pretty girl. "Erm, I'm sorry."

"Ichigo!" the girl said, seeming to know him.

The Senkaimon left and Ichigo stood up, bringing the girl with him. As he stood up, he got a good look at the one who had trampled him. She was very pretty with dark red hair pulled back into a ponytail, a white sash tied about it. He was surprised to find her forehead had some fanciful tattoos; in fact, he was surprised her quite large breasts were sporting tattoos as well. Finding himself staring, he looked away with a blush and fiddled with his feet.

"I've never seen you before, do I know you?" he asked.

"What do you mean? I'm your best friend, or so I thought." The girl said, putting her hands on her hips.

"We've never met." Ichigo said with a confused look.

"You can't tell it's me?"

"Who are you supposed to be?"

"_Renji_?" Rukia said with a surprised look at her friend.

"Of course. Why are you staring at me like that?"

"Have you iseen/i yourself?" Rukia practically screeched.

Renji blinked and then looked down at himself and squeaked, covering his breasts with the rest of his shihakusho.

"Wh- what the hell happened to me!? My voice! My body… My _pride_." he said, looking like he was about to fall over.

Ichigo ignored the conundrum beside him as he looked at the second person that had come in with Renji. It was a taller woman, jet black hair and piercing eyes. She was quite astonishingly regal, though she wasn't as endowed as her friend. He was surprised to see her with a white overcoat to proclaim her as captain, for he thought he met all thirteen of them besides the three renegades. The woman turned to him and gave him a glare that no other person but one could do.

"By-_Byakuya_?!" he blubbered, pointing and stepping back.

Byakuya lifted an eyebrow as Rukia twirled around and gasped.

"Nii-sama! Or is it, Nee-sama?" she said cautiously, truly not knowing what she should do.

"Captain will suffice." He said, his voice still lifeless even though he was a woman. "I will try to explain once we are not here."

"We were just heading to Urahara's Shop, Kuchiki-sama, if you wanted to accompany us." Orihime said, keeping calm.

He gave a nod and they followed them back to the shop.

* * *

As soon as Urahara saw them he burst into laughter, seeming to know exactly who the two were before they even opened their mouths. He smacked his fan on his leg as he laughed hysterically. Rukia grabbed her brother's hand to keep him from flying off the handle at the man, for she could see in his eyes that he was ready to pull out his sword. As she held his hand, she noticed how different it was from the usual big, strong and calloused hand she was used to. It was fair, dainty, soft…

Once Urahara grabbed his bounds, he wiped his tears away and then set to going straight to business.

"This is most unfortunate indeed. How did this happen?"

"Who knows? All I know is that a Hollow attacked, pretty fierce one, near our squad so the captain, some other men, and I went to dispatch it. It was a pretty difficult Hollow and I eventually released my shikai but when I brought it out, a puff of smoke overtook me and I fell flat on my back. I opened my eyes and continued to fight until it was over. I had looked over at the captain since he had also released his shikai and I noticed he was not… a man anymore."

Rukia looked at her brother as he daintily but sophisticatedly sipped the tea that had been given him when he entered the shop. Renji frowned. "Why don't I get tea?"

"Cuz you're a freeloader and you don't deserve tea when you're here pretty much all the time." Jinta said, hitting Renji in the back. "Just because you got turned into a girl doesn't mean you've changed your ways."

"Why I-"

"Renji, your shihakusho is falling." Ichigo said, turning away with a fierce blush again.

Renji looked down and frowned at his too big shihakusho as it had fallen down his shoulder and revealed a breast.

"That's hard to get used to. No wonder Matsumoto just lets hers hang out…"

Rukia rolled her eyes as Ichigo tried hard not to look at him.

Byakuya set his tea down and looked at Urahara.

"Head Captain Yamamoto felt that we should ask for your advice on the matter, considering this might turn into a problem. Mayuri had mentioned that he had something for those with bankais or higher but we only used our shikai."

Everyone stared at the usually quiet Byakuya and he stared at them with no expression. Urahara tittered behind his fan.

"Seems the gender change has caused you to be as talkative as a woman." Byakuya only narrowed his eyes at him. "Now, now… What is it that he wants you two to find out?"

"From what I gathered, he wants to know why this happened and why it happened in the shikai state when it was supposed to be in the bankai state. As well as why we didn't change the hell _back_!"

Urahara leaned back and fanned himself slowly.

"Well, I won't know anything until I see for myself. The only way I can do that is if someone goes there… How did it all start do you think?"

"I think it was that cloud that is in the Soul Society that came from the Research and Development Center. I think it permeated the air…" Renji said, looking off in the distance.

"Is that so?" Urahara said, looking at Ichigo and Rukia.

Ichigo made a face and shook his head.

"I'm not doing anything."

"Yes, you are. We need your help. We can't have everyone turning and staying that way, now can we? I won't know until you show me and I can do my own experiment on things."

"I'm not your guinea pig."

"Ichigo!" Renji yelled, grabbing Ichigo by the shoulders as he yelled. "You have to help us! I don't want boobs! Think of our pride!"

"That's exactly why I don't want to be in the same situation!"

"Please!"

"Get off me!"

Renji didn't move but then made a face and pressed himself against Ichigo's chest.

"Come on _Ichigo_, do it for me…"

"Get off me you idiot!" he said, pushing Renji off of him. "I'm not going to do it!"

"Um…" Everyone looked at Orihime and she put her hand down. "If you need help, I can try. Urahara-san, you said that my powers were equal to a shikai once, yes?"

"Yes."

"I'll help you, Renji-chan… er, -kun."

"Orihime, I won't let you go through that."

"You don't have to do that, Orihime-chan." Rukia said.

"Well, Renji-kun and Byakuya-sama need our help and I understand that Ichigo doesn't want to help. But the question still is why did it happen in the shikai state, yes? Maybe it only happens in the shikai state for those with a bankai as well. Since my power is only as much at the shikai, it wouldn't hurt to see."

Urahara nodded. "That works for me."

"Now hold on-"

"Thanks, Orihime-chan! You're such a great person!"

"Hey! You can't do that to her!"

"Can't I?" Urahara said, looking over the fan with a dangerous look. "If you won't help I will take those who can."

Ichigo was taken aback and then sighed, looking at Orihime.

"Alright… Fine, I'll help."

"Great! Let's get going."

* * *

orihime is a little too happy to help. i'd be like ichigo and be like, uh, no i don't wanna find that out but oh well


	3. Chapter 3

i apologize for the wait and her is the next update. please keep in mind that fanfiction is not my mainstream writing skill, i also have original stories as well as published books that i work on. i get to these as fast as my brain can get into the mindset of the plot of the story as well as the mood. thank you for being patient.

* * *

As they all waited for the Senkaimon, Ichigo turned to Orihime.

"Orihime, I can't let you go through this. What if it _isn't_ just those who possess a bankai? I mean, if we don't figure something out then you could be a man."

"I know. Thank you for worrying, Ichigo, but our friends are in trouble and I want to help them. It's the least I can do for what they've done for me." She said, touching her hand to her heart.

Renji put his hand to his chest.

"Orihime-chan, that was _so sweet_. Thank you for caring!" He gasped. "Damn it! See what this is doing to us? Ichigo, I sound like Matsumoto." He said as he grabbed Ichigo's shoulders and acted like he was crying.

Ichigo made a face as Byakuya rolled his eyes, pointing his sword at the air. A Senkaimon appeared and opened and Urahara waved with the fan to them.

"Bring me some samples or at least change genders and come back so I can do some studies."

Ichigo made a face at the crazy scientist and they all walked through the Senkaimon. As soon as they were on the other side, they began to run as The Cleaner tunneled its way toward them. Ichigo found it hard to keep his eyes off Renji as he tried to keep his breasts from coming from under his shihakusho since he was making a spectacle of himself in the process. He looked over at Byakuya, who didn't seem to have much of the same trouble.

"Yo, Byakuya, is there a reason why Renji's having such a hard time with is new boobs?" he said, thumbing to his friend.

Byakuya glanced slightly at Renji and then frowned.

"I suppose it might be because his are bigger than mine."

Rukia tried to stifle a laugh as Renji gave his superior a glare.

"You're not very nice, Captain."

"I am simply stating fact. You seem to be having a bit of trouble, Lieutenant."

Renji proceeded to hold a boob in each of his hands as he ran, which made Rukia release the laugh she'd been trying to hold in and Orihime giggled.

"I understand how you feel, Renji-kun." She said as she ran normally, having been used to them.

"I don't understand how you and Matsumoto deal with these things! They're so big and just in the way."

Ichigo tuned them out as they approached the opening to get into the Soul Society. As they started coming out, they saw the figures moving rapidly but they were going too fast to see that they were trying to flag them to a halt. At that, they all jumped through and the huge door closed behind them.

"You should have turned back!" the Soul Reaper said as he ran to them. Seeing Byakuya and Renji he made a face and turned to the other three. "You should have not come in here. There is an epidemic going around."

"Yeah, we noticed." Ichigo said, thumbing to Renji, who was still having problems.

"Has there been any more 'changes' lately?" Renji asked.

"A couple have changed but they have tried to keep those who have shikais or higher from releasing their zanpakutos unnecessarily."

They all nodded and then headed toward the Seireitei.

Once they all got to the Seireitei, they found some of the captains heading toward the Head Captain's chambers. Byakuya stopped Ukitake.

"What's going on?"

Ukitake blinked for a moment, trying to take in who was talking to him. Once he realized that it was Byakuya, he cleared his throat.

"I apologize; I didn't realize it was you, Kuchiki-san." Byakuya just lifted an eyebrow. "To answer your question though, the Head Captain has called for a meeting of all the captains so that Captain Kurotsuchi can explain what we are dealing with. As I can see from your appearance, you are not immune to the strange happenings of today."

"Not quite." He said.

Ukitake nodded and then realized that the other three were there. He smiled at them.

"Kuchiki-san, Ichigo, Orihime-san, so good to see you."

"And you, Ukitake-sama." Orihime said with a wave.

Ukitake nodded and Byakuya strode away toward the captain's chambers for the briefing.

"You all can stay in Squad Thirteen barracks if you like until we all get out of the captain's meeting."

They nodded and headed toward Rukia's squad.

* * *

As the captain's assembled, Byakuya was happy to find that there were others who had fallen victim to the cruel gender switching as well. He wasn't surprised to find that what could only have been Kenpachi was now a menacing and thankfully fully clothed woman. He was thick with muscle but was still a halfway decent looking woman. He saw that even usually level headed Toshiro had also been turned into a woman. He seemed to have the same problem that Renji had and was looking around nervously, trying desperately to keep his new breasts from flying from his shihakusho since they seemed to be very large.

Byakuya looked down at his own and found it odd that he was perturbed by the fact that he didn't gain any bigger ones as his counterparts had. Why, he had no idea, but he was slightly grateful because they seemed to be having lots of trouble with them.

As he looked around, it didn't look like anyone else had a problem except there was only one real woman in the line and that was Unohana. So where was Soi Fon? He looked in the spot where the usual spitfire female captain would be and found a young man standing there with black hair pulled back into a small ponytail with the same yellow ribbon tied around his waist. There were two longer hairs wrapped in cloth on his shoulders and he was wearing Chinese looking slippers instead of the Soul Reaper sandals. He made a mental note that Soi Fon looked good as a man and then turned to the Head Captain.

"It seems that things have gotten a little out of control within the Soul Society. As we can all see, some of the captains did not get the warning in time and have thus… _changed_."

"_Changed_?!" Soi Fon yelled, her voice deep since she was now a boy, as she looked at the Head Captain. "Captain Yamamoto, this is a perversion of nature! We can't live like this!"

"Precisely. Therefore, I have asked Captain Kurotsuchi to please explain to us what is going to happen as he tries to find something to return those who have changed back to their regular selves. Captain Kurotsuchi…"

The blue faced man sighed loudly as if he were inconvenienced terribly and looked at everyone.

"I was trying to make a formula to increase our strength tenfold when we fought in our bankai state. I wasn't finished with the serum yet before it was… decidedly dropped and had spread into the Seireitei. The strength is there but I had one last component to figure out and that was the gender. I had to make sure that when the serum effected those with bankais that this very thing didn't happen. Since we have both genders who can achieve the bankai state, I needed it to be able to differentiate."

"That's all fine and dandy, Creep, but why did this happen in the first place? What would make us change genders completely?" Soi Fon said, leaning forward to look at Captain Kurotsuchi.

"All I can guess is that since it was incomplete and I had not put in the indicator for it, it decided that when the states were met, it would change the genders."

"Is there a way to reverse this process?" Yamamoto asked.

"Of course. The problem is that I need a specimen and no one will volunteer."

"That's for our own safety." Toshiro said. "Who wants to fear you getting knife happy and cutting us up?"

"Agreed. Why don't you just use bankai and turn _yourself_ into a girl?" Soi Fon said.

Captain Kurotsuchi chuckled. "I wish that were the case, Captain Soi Fon but it seems that all the other experiments that I've done on myself keeps me immune to others. Besides, I usually practice on Nemu but she isn't real so it won't effect her either."

"I didn't use my bankai; why am I a woman?" Byakuya voiced from the line.

Toshiro nodded. "That's right! I wasn't even in my bankai state when I turned. I mean, if we turn into girls now will be turn into something different later?"

"Did we turn because we also have bankais as well as shikais?"

"No. It is meant to work on the most powerful attack that one possesses. If a person only has shikai then it makes their shikai stronger as well as bankai. Since you just used the shikai state, you are only at half the strength it would be. This is apparently a fluke in the serum's development."

"How long will we be like this?" Kenpachi asked, looking at his nails. "I was already strong so why do I have to suffer and be a woman like these wimps?"

"Well if you weren't in a state of constant release you may not have changed." Soi Fon said.

"Keh." He said, crossing his arms.

Head Captain Yamamoto hit his cane to the floor.

"Enough. For the time being, we must halt all practicing activities of zanpakuto and training. We can't risk someone else turning because they were training and such. As for now, those who have not changed, please pass down your squads for everyone to try and stay away from shikais and bankais if anything happens. As for those who have, Captain Kurotsuchi only needs a sample of blood and he will begin to work on a serum." At that, the Head Captain stomped his cane onto the floor and ended the discussion.

The other captains who had not been effected left which left Kurotsuchi with Soi fon, Byakuya, Toshiro, and Kenpachi. The captain rubbed his hands together, looking at the foursome.

"Well, this is promising. You have no become my experiments thus far. The whole of Seireitei counts on your bodies today."

Byakuya was not amused.


End file.
